Kubuntu20.04 apt-get update error

[am365]

basically, I'm a super noob to Kubuntu, and when I go to update using Sudo apt-get update. I get the following code:

~$ sudo apt-get update
Ign:1 cdrom://Kubuntu 20.04.1 LTS _Focal Fossa_ - Release amd64 (20200731) focal InRelease
Err:2 cdrom://Kubuntu 20.04.1 LTS _Focal Fossa_ - Release amd64 (20200731) focal Release
Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used t
o add new CD-ROMs
Hit:3 http://archive.canonical.com/ubuntu focal InRelease
Hit:4 http://archive.ubuntu.com/ubuntu focal InRelease
Get:5 http://archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Hit:6 http://archive.ubuntu.com/ubuntu focal-backports InRelease
Get:7 http://archive.ubuntu.com/ubuntu focal-security InRelease [109 kB]
Reading package lists... Done
E: The repository 'cdrom://Kubuntu 20.04.1 LTS _Focal Fossa_ - Release amd64 (20200731) focal
Release' does not have a Release file.
N: Updating from such a repository can't be done securely and is therefore disabled by defau
lt.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Any help would be greatly appreciated!!

[GreyGeek]

Do you have muon installed? If so, open muon and then open the repository. It will look like this:

Notice that the CDROM is not checked. If your's is then uncheck it and click the close button.
Otherwise, open /etc/apt/sources.list with nano and put a "#" in front of the cdrom line.
[quote]
deb http://us.archive.ubuntu.com/ubuntu/ focal restricted main
deb http://us.archive.ubuntu.com/ubuntu/ focal-updates restricted main
# deb cdrom:[Kubuntu 20.04 LTS _Focal Fossa_ - Alpha amd64 (20200104)]/ focal main multiverse restricted universe

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal main restricted
...
{/quote]
and save the file. Then try "sudo apt ...whatever".

Here is my entire sources.list file

deb http://us.archive.ubuntu.com/ubuntu/ focal restricted main
deb http://us.archive.ubuntu.com/ubuntu/ focal-updates restricted main
# deb cdrom:[Kubuntu 20.04 LTS _Focal Fossa_ - Alpha amd64 (20200104)]/ focal main multiverse restricted universe

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal main restricted

## Major bug fix updates produced after the final release of the
## distribution.
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ focal universe
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal universe
deb http://us.archive.ubuntu.com/ubuntu/ focal-updates universe
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://us.archive.ubuntu.com/ubuntu/ focal multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal multiverse
deb http://us.archive.ubuntu.com/ubuntu/ focal-updates multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://us.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
deb http://archive.canonical.com/ubuntu/ focal partner
# deb-src http://archive.canonical.com/ubuntu/ focal partner

deb http://security.ubuntu.com/ubuntu/ focal-security main restricted
# deb-src http://security.ubuntu.com/ubuntu/ focal-security main restricted
deb http://security.ubuntu.com/ubuntu/ focal-security universe
# deb-src http://security.ubuntu.com/ubuntu/ focal-security universe
deb http://security.ubuntu.com/ubuntu/ focal-security multiverse
# deb-src http://security.ubuntu.com/ubuntu/ focal-security multiverse

# This system was installed using small removable media
# (e.g. netinst, live or single CD). The matching "deb cdrom"
# entries were disabled at the end of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.
# deb http://ca.archive.ubuntu.com/ubuntu/ focal-proposed multiverse universe restricted main

[claydoh]

Do you have muon installed? If so, open muon and then open the repository. It will look like this:
[ATTACH=CONFIG]9159[/ATTACH]
Notice that the CDROM is not checked. If your's is then uncheck it and click the close button.

If you don't have Muon installed, you can get to this from Discover, via Settings, then look for Software Sources.